The invention relates to a system for recycling for the purpose of re-utilizing the components of defective or spent fluorescent tubes.
For lighting purposes in offices, in public areas, workshop halls etc., one usually uses fluorescent lamps that are made of a straight glass tube, whose inside circumference is coated with a fine luminescent powder and whose interior is filled with a low pressure gas. This type of tubular fluorescent lamp is called a fluorescent tube. The ends of the glass tube are sealed and provided with a metal connecting base, which bears contact pins. These universal fluorescent tubes have only a limited life and, therefore, rapidly fall into a defective or spent state. Their components, namely the glass tube, the connecting base and the content material, namely phosphors and mercury, are largely recyclable. For this reason the fluorescent tubes are collected for recycling the components on pallets with suitable superstructures, on which the tubes are deposited in ordered layers.
To recycle the components of these fluorescent tubes there exists a system that comprises a raised longitudinal stage, on whose one end the pallets with the fluorescent tubes can be deposited. Attached to the pallet region in the longitudinal direction is an essentially closed housing, which has a lift beam conveyor, which conveys the fluorescent tubes step-by-step forward, moving them past several processing stations in the housing.
In the feed station the fluorescent tubes are fed manually to a short chain conveyor, where at one end of the conveyor the fluorescent tubes are transferred to the lift beam conveyor.
The processing stations in the housing comprise, first of all, a perforating station, in which stationary oxyhydrogen burners direct a very concentrated thin flame on the glass tube in the vicinity of the respective cap and burn a small hole in the glass tube. The air can flow through this small hole into the fluorescent tube in order to produce a pressure equilibrium.
Then the fluorescent tubes are carried past a severing station, where the fluorescent tubes are turned and the glass tube in the vicinity of the respective cap is severed, i.e. cracked off, using another burner.
Next is a blow-out station, in which a strong blast of air is sent from one side through the glass tube, which has been freed of its caps. The air blows out the bulk of the fine luminescent powder adhering to the inside circumference of the glass tube through the other end of the glass tube.
Finally the cleaned glass tube is comminuted into small free-flowing fragments or splinters.
The caps, the glass and optionally the content materials are collected and fed to recycling. When the recycling of the content material cannot be justified from an economic view point, dumping, e.g. underground landfill, may also be considered.
The existing system has functioned for years satisfactorily, but its efficiency is limited. Namely the single fluorescent tube must remain in the perforating station and in the severing station until the burner has created the hole. This intermittent method is time-consuming.